Effects of diffuse fatty infiltration of the liver on portal vein flow hemodynamics

PURPOSE: To investigate the effects of various degrees of diffuse fatty infiltration of the liver on portal vein blood flow with Doppler sonography. METHODS: One hundred forty subjects were examined with color and spectral Doppler sonography. The subjects were divided into 4 groups of 35 subjects each according to the degree (normal, grade 1, grade 2 and grade 3) of hepatic fatty infiltration assessed on gray-scale images. The portal vein pulsatility index (VPI) and time-averaged mean flow velocity (MFV) were calculated for each subject. VPI was calculated as (peak maximum velocity - peak minimum velocity) / peak maximum velocity. RESULTS: VPI and MFV values were, respectively, 0.32 +/- 0.06 and 16.8 +/- 2.6 cm/second in the normal group, 0.27 +/- 0.07 and 14.2 +/- 2.2 cm/second in the group with grade 1 fatty infiltration, 0.22 +/- 0.06 and 12.2 +/- 1.8 cm/second in the group with grade 2 fatty infiltration, and 0.18 +/- 0.04 and 10.8 +/- 1.5 cm/second in the group with grade 3 fatty infiltration. There was a negative inverse correlation between the grade of fatty infiltration and both VPI (f = 55.3, p < 0.001) and MFV (f = 43.9, p < 0.001). CONCLUSION: The pulsatility index and mean velocity of the portal vein blood flow decrease as the severity of fatty infiltration increases.     

非酒精性脂肪性肝病门脉系统血流动力学变化的实验研究

目的 研究非酒精性脂肪性肝病(NAFLD)大鼠门静脉系统血流动力学改变.方法 将64只大鼠随机分为对照组和模型组,模型组动物通过高脂饮食建立非酒精性脂肪性肝病大鼠模型,应用超声多普勒技术测量不同时期门静脉(PV)及脾静脉(SPV)血流动力学指标,并与病理检查结果相比较.结果 8周时对照组与模型组脂变积分有明显差异(P＜0.05),12、16、22周模型组均有明显的脂肪变,12周模型组开始出现PV内径增宽,流速减慢.PV内径与脂变积分呈正相关,PV流速、SPV流速与之呈负相关.门静脉流量无统计学差异.结论 超高频多普勒超声町以较敏感地检测NAFLD大鼠不同时期PV系统血流动力学变化.     

用超声研究脂肪肝的血流动力学变化

目的应用彩色多普勒技术探讨脂肪肝的血流动力学变化及与脂肪肝程度的关系。方法运用彩色多普勒超声探测102例脂肪肝患者肝静脉、门静脉血流参数,分析脂肪肝病变程度及临床意义。结果重度脂肪肝的肝静脉、门静脉血流速度均低于正常值,并与脂肪肝的程度成反比。结论彩色多普勒超声技术对脂肪肝病变程度有较好的诊断价值。     

Cavernous transformation of the portal vein (CTPV): role of color Doppler sonography in the diagnosis

Objective: The aim of this study was to investigate the hemodynamics of cavernous transformation of the portal vein (CTPV) using color Doppler sonography and to correlate it with sonographic findings and clinical manifestations. Methods: Using color Doppler sonography, we studied 25 patients who satisfied the sonographic diagnostic triad of CTPV and compared clinical, sonographic, and color Doppler findings. We also compared the hemodynamics of the liver vasculature in a group of CTPV patients with that in a group of normal subjects. Results: We could differentiate five cases of dilated hepatic artery without formation of CTPV from 20 cases of CTPV. In 13 cases of CTPV, the cause of the portal vein thrombosis prior to CTPV could be determined. Two types of CTPV were distinguished: linear type (small diameter without tortuosity) and tortuous type (large diameter with tortuosity). There were no particular tendencies in the cause or distribution between the two groups, but the flow velocity was significantly higher in the tortuous type than in the linear type. Slow continuous flow with little or no respiratory variations was observed in CTPV by color Doppler sonography in agreement with previous reports, and the velocity of CTPV was slower than that of the portal flow in normal subjects. The flow velocity was not related to the cause or the presence of developed collaterals, and the flow direction was always hepatopetal. Conclusion: Color Doppler sonography was considered to be the most useful modality for the diagnosis and comprehension of the hemodynamics of CTPV.     

Color Doppler velocity profile assessment of portal hemodynamics in cirrhotic patients with portal hypertension: correlation with esophageal variceal bleeding

PURPOSE: Using the color Doppler velocity profile (CDVP), we investigated portal hemodynamics and their relationship with esophageal variceal bleeding (EVB) in patients with cirrhosis and portal hypertension. METHODS: The hemodynamics of the portal trunk, right anterior portal branch, and splenic vein were evaluated in 69 cirrhotic patients with portal hypertension and 46 healthy volunteers. The CDVP, a recently developed Doppler software, was used to measure blood flow velocity and flow volume; evaluate the spatial distribution of flow velocities in the cross-section of a vessel (velocity profile), as reflected by the profile parameter (n); and assess changes in flow volume over time (flow profile). The congestion index was calculated by dividing the cross-sectional area by the maximum cross-sectional velocity (CSVmax). The hemodynamic features were compared between patients without a history of EVB [EVB(-)] and those with a history of EVB [EVB(+)], and a logistic regression model was employed to identify factors associated with EVB. RESULTS: Compared with the healthy group, the cirrhotic group had a significantly lower mean CSVmax in the portal trunk and right anterior portal branch (both p < 0.01), a significantly elevated mean flow volume in the splenic vein and portal trunk (both p < 0.01), a significantly elevated mean ratio of splenic vein flow volume to portal trunk flow volume (SV/PT) (p < 0.001), and a significantly greater mean congestion index in the portal trunk, right anterior portal branch, and splenic vein (all p < 0.01). In the cirrhotic group, there was a significantly higher incidence of a flat flow pattern in the right anterior portal branch and a phasic flow pattern in the splenic vein than in the healthy group (both p < 0.01). Among cirrhotic patients, the EVB(+) group had a significantly greater mean flow volume in the splenic vein (p < 0.01), greater mean SV/PT (p < 0.01), greater mean spleen size (p < 0.05), and lower mean portal trunk n value (p < 0.05) compared with the EVB(-) group. Logistic regression analysis revealed that the SV/PT and portal trunk n value were independent EVB-related factors. CONCLUSIONS: The results suggest that portal hemodynamics in cirrhotic patients are characterized by passive congestion and increased blood flow. However, these 2 features had different preponderances in different parts of the portal venous system. Increased flow in the splenic vein may be the primary source of increased portal flow and may play a role in the development of EVB. The SV/PT and portal trunk n value may be valuable factors for predicting EVB.     

肝硬化食管静脉曲张破裂出血患者门静脉血流参数的变化

目的 探讨彩色多普勒超声预测肝硬化门静脉高压症(cirrhotic portal hypertension)患者食管静脉曲张破裂出血的应用价值.方法 肝硬化门静脉高压症患者81例,根据有无出血史分为出血组(36例),非出血组(45例).应用彩色多普勒超声分别检测两组的门静脉(pv)和脾静脉(sv)内径(Dpv、Dsv)、血流动力学参数并进行对比分析.结果 门静脉和脾静脉的内径、血流速度(Vpv、Vsv)及脾静脉的血流量(Qsv)在两组间差异均有统计学意义(P<0.05),但门静脉血流量(Qpv)在两组间差异无统计学意义(P>0.05).结论 彩色多普勒超声检测肝硬化门静脉高压症患者门静脉和脾静脉内径及血流动力学参数,对预测肝硬化门静脉高压时食管静脉曲张破裂出血是有价值的.     

Hemodynamic effects of a prostacyclin analog (iloprost) on portal flow velocity and volume and visceral artery circulation in patients with lower limb arteriopathy

Previous studies demonstrated that iloprost improves the peripheral circulation. In this study, we examined, by Doppler sonography, portal flow velocity (cm/s) and volume (mL/min), and resistance index (RI) of visceral arteries in 23 patients before and after 7 days of iloprost infusion. Statistically significant hemodynamic changes were only seen in portal vein (pre-iloprost vs. post-iloprost treatment mean portal flow velocity and volume values: 23.9 cm/s vs. 29.0 cm/s, p < 0.001 and 1824.6 mL/min vs. 2294.4 mL/min, p < 0.001, respectively). On the other hand, the interlobar renal artery RI, reduced after iloprost treatment in most patients, was not statistically significant; conflicting results were obtained on the hepatic and mesenteric arteries. Our results indicate that iloprost significantly increases portal flow velocity and volume. The understanding of the mechanism through which iloprost plays a role in portal microcirculation could be useful for its new medical indications in liver hemodynamic disorders.     

肝硬化门静脉高压门脉血流动力学检测及其临床意义

目的：探讨肝硬化门脉高压患者门脉血流动力学状态并分析其与Child-Pugh肝功能分级的关系。方法：利用多普勒超声技术检测了100例肝硬化门脉高压患者及24例正常人门脉血流动力学状态,并将100例肝硬化门脉高压患者按Child-Pugh肝功能分级分析两者之间的关系。结果：肝硬化门脉高压门脉血流动力学检查与正常对照组比较、门脉高压组门静脉（PV）内径明显增宽、血流速明显减慢、血流量参数明显增加,差异有显著性意义（P＜0．01）;脾静脉（SV）肠系膜上静脉（SMV）内径（D）、血流速度（V）、血流量参数（Q）也有类似改变。A、B、C三级肝硬化的PV内径,按A、B、C顺序显示门静脉宽度逐渐增宽,C级的Dpv较A、B级均有显著性增宽（P＜0．05）,A、B级间差异无显著性意义（P＞0．05）,但B级较A级也有增宽趋势,按A、B、C顺序显示 门静脉血流速度逐渐降低,且各级间比较差异有显著性意义（P＜0．05）。A、B、C级的Qpv相互比较无统计学差异（P＞0．05）。结论多普勒超声检测门脉血流动力学有助于评价肝硬化患者的肝储备功能、门静脉高压程度及预后。     

双功多普勒检测门脉血流动力学的临床应用

应用双功多普勒检测了３２例正常对照者，３８例慢性肝炎，１７例肝硬化和３２例原发性肝癌患者的门脉血流动力学，发现肝硬化，原发性肝癌组门静脉内径显著大于正常对照组和慢性肝炎组；门脉血流速度则三组患者均显著低于对照组；门脉血流量仅慢性肝炎组显著低于对照组；三组患者的门脉充血指数均显著大于对照组。本文初步探讨了门脉血流动力学检测的临床意义及各种生理因素对门脉血流的影响。     

Value of Doppler sonography in assessing the progression of chronic viral hepatitis and in the diagnosis and grading of cirrhosis.

OBJECTIVE: The purpose of this study was to evaluate the value of Doppler sonography in assessing the progression of chronic viral hepatitis and in the diagnosis and grading of cirrhosis. METHODS: Abdominal sonographic and liver Doppler studies were performed in 3 groups: 36 patients with chronic viral hepatitis, 63 patients with cirrhosis, and 30 control subjects with no evidence of liver disease. A series of Doppler indices of hepatic vascularity, including portal vein velocity, portal vein pulsatility score, flow volume of the portal vein, resistive and pulsatility indices of the hepatic artery, modified hepatic index, hepatic vascular index, waveform of the hepatic vein, and focal acceleration of flow, were measured and correlated with liver and spleen size, portal and splenic vein diameter, and presence of ascites and collateral vessels. These indices were compared across the 3 study groups and within the patient groups with respect to presence of inflammation, fibrosis, and steatosis, as determined by histologic evaluation. RESULTS: The most useful indices were portal vein velocity, the modified hepatic index, and nontriphasic flow in the hepatic vein, which were helpful in distinguishing patients from control subjects. Hepatic vascular and modified hepatic indices were useful for differential diagnosis of cirrhosis and chronic viral hepatitis. However, all measurements were limited in their ability to determine the severity of chronic hepatitis. CONCLUSIONS: Doppler sonography is sensitive to hemodynamic alterations resulting from inflammation and fibrosis, and if sonography is the study of choice to follow the progression of hepatitis, it will not be adequate without Doppler imaging. Doppler sonography has high diagnostic accuracy in cirrhosis despite some false-positive conditions. However, it has a limited role in clinical grading.     

门静脉血流动力学改变与肝组织纤维化图像定量分析的相关性研究

目的探讨门静脉血流动力学改变与肝组织病理纤维化图像分析的相关性。方法用彩色多普勒超声测定106例慢性病毒性肝炎患者的门静脉主干内径、血流峰值速度、平均速度及血流量。所有患者均做肝穿刺活检。采用计算机图像分析系统对肝组织标本进行纤维化定量测定,同时根据常用的慢性肝炎分级分期标准对肝纤维化进行分期。结果肝纤维图像定量测定与纤维化病理分期有良好的相关性(r=0.690,P<0.01)。门静脉主干内径、血流峰值速度、平均速度与肝组织纤维化分期及纤维化图像定量分析结果均呈显著性相关(P<0.01),而门静脉血流量则与上述两者均无显著性相关(P>0.01)。结论多普勒超声探查门静脉血流动力学改变可反映肝纤维化的病理进程,对无创性评价慢性肝炎肝纤维化程度有重要意义。     

Measurement of left portal vein blood-flow velocity by Doppler sonography in a patient with acute fatty liver of pregnancy

Acute fatty liver of pregnancy was diagnosed in a 32-year-old primipara in her 34th week of gestation. The pulsed Doppler sonogram showed that mean maximum portal blood-flow velocity obtained at the umbilical-point of the left portal vein (the U-point) decreased during the acute phase of the disease and returned to the normal range accompanied by improvement in her condition. Findings of portal blood dynamics obtained by pulsed Doppler sonography and those of the hyperechoic hepatic parenchyma obtained by conventional sonography could prove useful in following up patients in their third trimester of pregnancy.     

非对比剂增强磁共振血管成像评价门静脉血流动力学的可行性研究

目的探讨利用多反转空间标记脉冲非对比剂增强磁共振血管成像(non-contrast-enhanced magnetic resonance angiography using spatial labeling with multiple inversion pulses,SLEEK-MRA)评估门静脉血流动力学的可行性。材料与方法纳入25例门静脉高压患者先后行SLEEK-MRA和彩色多普勒超声(color doppler ultrasonograohy,CDUS)检查,SLEEK-MRA序列采用不同血流抑制反转时间(blood suppression inversion time,BSP TI):600、900、1200、1500 ms。对门静脉分支显示情况进行评级并与通过与CDUS血流速度测定结果进行相关性分析。依据CDUS所测流速将患者分组,并比较各组患者分支显示评级情况以及BSPTI参数应用情况。结果门静脉左、右支在全部BSPTI设定时SLEEK-MRA的分支显示评级均与CDUS所测得血流速度呈现出显著相关性。在门静脉流速明显减慢组患者,分支评级明显低于流速正常或轻度减慢组,应用BSP TI值明显高于流速正常或轻度减慢组。结论 SLEEK-MRA在提供高质量门静脉形态学成像同时,具有提示门静脉血流动力学变化的潜力,通过SLEEK-MRA获取血流动力学信息是可行的。     

Visualization of blood flow in hepatic vessels and hepatocellular carcinoma using B-flow sonography

PURPOSE: A B-flow sonographic technique was recently developed to provide direct visualization of blood flow with gray-scale sonography. Compared with color Doppler sonography, B-flow imaging has wideband resolution and a high frame rate. The purpose of this study was to evaluate the usefulness of B-flow sonography for visualizing blood flow in hepatic vessels and tumor vascularity in patients with liver cirrhosis or hepatocellular carcinoma (HCC). METHODS: Twenty-five patients with liver cirrhosis, including 15 with HCC, were studied by B-flow and color Doppler sonography. Blood-flow detection rates in portal veins and hepatic arteries and tumor vascularity in HCC were analyzed, and the 2 methods were compared. RESULTS: Using B-flow, blood flow was visualized in the portal vein in 23 (92%) of 25 patients and was visualized in the hepatic artery separately from the portal vein in 9 (36%) of 25 patients. The blood-flow signals were visualized only within vessels, never "bleeding" outside the vessel's lumen. Blood flow in the portal vein was observed with color Doppler sonography in all 25 patients, but the hepatic artery was never clearly separated from the portal vein. Vascularity within the HCC tumor was detected in 9 (60%) of 15 nodules with B-flow imaging, and fine arteries flowing into the tumor were observed in 6 nodules. Color Doppler sonography detected blood flow in 13 (87%) of the 15 HCC nodules. CONCLUSIONS: Blood flow in hepatic vessels and tumor vessels of HCC were visualized with B-flow sonography. B-flow sonography is a potentially useful technique for the evaluation of liver vascularity and intratumoral vessels.     

二维彩色多普勒超声观测肝硬化门脉高压症脾肺固定合并门奇断流术前后门脉系统血流动力学改变

本文应用二维彩色多普勒超声对8例肝硬化门脉高压症的门脉系统血流动力学在脾肺固定合并门奇断流术前后分别进行定量研究和对比分析。结果表明术后门静脉及睥静脉的内径、平均流速和血流量比术前明显缩小和降低(P<0.001～0.05),门、睥静脉的血流量减少,两者呈正向相关关系(r=0.93,p<0.001)。结果认为该手术能使门静脉系统发生断流、分流和减流.使门静脉系统血流量减少,门脉高压及脾胃区高压缓解。双功能超声对门脉高压症手术方法的选择及效果的评价是一种有临床应用价值的无创性检查方法。     

Correlation of MRI liver volume and doppler sonographic portal hemodynamics with histologic findings in patients with chronic hepatitis C

PURPOSE: The purpose of this study was to correlate portal hemodynamics on sonography and liver volume on MRI with histologic findings in asymptomatic patients with chronic hepatitis C. METHODS: Portal blood flow in the left and right portal branches in 20 healthy volunteers and in 26 patients was measured using Doppler sonography during both fasting and postprandial states. Total liver and right-and left-lobe volumes were determined using MRI. The ratio between portal blood flow and liver volume determined the "portal flow index" of the right and left lobes. RESULTS: We observed a statistically significant difference (p < 0.01) between the volunteers and patients in the mean left-lobe volume (352 +/- 81 cm(3) versus 544 +/- 159 cm(3)) and in the mean left portal flow index (1.1 +/- 0.2 ml/minute/cm(3) versus 0.69 +/- 0.2 ml/minute/cm(3)) as measured before the subjects ate. After a meal, the portal blood-flow volume in the right lobe was similar in the 2 groups but in the left lobe was significantly lower in the patients (p = 0.0009). The left postprandial portal flow index was inversely correlated with the grade of liver fibrosis (r = 0.533). CONCLUSIONS: The left-lobe volume (positive predictive value, 83%; negative predictive value, 72%) and left postprandial portal flow index (positive predictive value, 86%; negative predictive value, 88%) are sensitive indicators of chronic hepatitis. The left postprandial portal flow index may be a useful test for differentiating patients with minimal or no fibrosis from patients with mild to severe fibrosis.     

Portal vein aneurysm: report of six cases and review of the literature

Portal vein aneurysm is very rare, and its relation to portal hypertension has been emphasized. We report six cases of portal vein aneurysm (five extrahepatic and one intrahepatic). All patients were asymptomatic and had no signs suggestive of portal hypertension; the lesion was incidentally detected by ultrasound. Color Doppler sonography showed a constant hepatopetal flow along the aneurysmal wall, which immediately led to the diagnosis. We stress the usefulness of color Doppler sonography for studying the hemodynamics of this vascular anomaly and briefly review the literature. Received: 29 December 1995/Accepted: 14 February 1996     

Contrast-enhanced Doppler perfusion index: clinical and experimental evaluation.

OBJECTIVE: To assess the potential of the power Doppler signal intensity rate of enhancement due to contrast agent wash-in for assessment of hepatic hemodynamics. METHODS: With the use of standardized settings, power Doppler sonography was performed before and after administration of a contrast agent. Video-recorded examinations were digitized for offline analysis on a personal computer. The temporal changes of the power Doppler signal intensity were quantified to provide contrast agent wash-in curves. The contrast-enhanced Doppler perfusion index was defined by the ratio of the wash-in gradient of the hepatic artery and portal vein as contrast-enhanced Doppler perfusion index = hepatic artery gradient/(hepatic artery gradient + portal vein gradient). The contrast-enhanced Doppler perfusion index was evaluated at 4 contrast agent doses in each of 14 patients with liver metastases and 3 patients with hemangiomas. An in vitro flow model was used to determine the relationships between the power Doppler rate of enhancement and flow in vessels of 4, 8, and 12 mm in diameter. RESULTS: In vivo, there was a significantly higher (P < .0001) mean contrast enhanced Doppler perfusion index in patients with liver metastases (mean, 0.59; 95% confidence interval, 0.54-0.63), compared with patients with hemangiomas (mean, 0.33; 95% confidence interval, 0.24-0.41). The corresponding coefficients of variations were 25% for patients with liver metastases and 31% for patients with hemangiomas. In vitro, the power Doppler rate of enhancement was proportional to flow speed and independent of vessel diameter. CONCLUSIONS: Measurement of the contrast-enhanced Doppler perfusion index may have potential in assessment of hepatic hemodynamics and focal liver disease.     

不同肝功能分级门脉高压症患者的门脉系统血流动力学变化

应用彩色多普勒血流显象检查４０例正常人及５０例门脉高压症患者门脉系统的血流动力学，其中２９例患者术中测自由门脉压，发现：门脉高压症门脉系统处于高阻力、高动力的血流淤滞状态；Ｃｈｉｌｄ－ＰｕｇｈＢ级患者的门脉系统的血流动力学多项指标既大于Ａ级又大于Ｃ级，可能与门体侧支循环的建立有关；门脉系统的高动力循环主要来自于脾静脉，门脉主干的血流量只是正常人的１．２倍，说明该症存在大量的门脉血肝前分流。     

彩色多普勒超声和能量多普勒超声对经颈静脉肝门-体静脉支架分流术后的评价

目的探讨彩色多普勒和能量多普勒超声在经颈静脉肝内门-体静脉支架分流术(TIPSS)后内支架血流动力学情况及其在随访中的价值。方法24例肝硬化门脉高压患者行TIPSS,术后应用彩色多普勒和能量多普勒检查72例次,测量支架的血流速度。结果随访3个月~2年,彩色多普勒和能量多普勒显示支架内的血流方向,频谱多普勒显示支架内以及门静脉和脾静脉的血流速度。从支架门静脉端到支架肝静脉端血流速度逐渐增加。1例患者多普勒血流显示支架内狭窄,为门静脉造影证实。与正常支架比较,狭窄支架的血流速度测值差异有显著性意义(P<0.05)。结论彩色多普勒和能量多普勒超声可以方便有效地检测TIPSS术后内支架的血流情况,是TIPSS术后定期复查和疗效判断的首选方法。